Monera, protoctists, fungi and plants.

The Monera Kingdom.The Monera Kindom contains unicellular prokaryotic organisms (without an organized nucleus), such as bacteria.

The vital functions of bacteria.

Nutrition: Some bacteria are autotrophic but most are heterotrophic and they feed in different ways:

Saprophytes: These live on decomposing organic remains and they become inorganic substances. In this way they enrich the soil.

Parasites: They feed on other living beings, harming them and causing infectious illnesses.

Symbionts: They live in close association with another living being and this produces a mutual benefit such as those which live in our intestine. Some bacteria live inside plants we eat, such as leguminous plants. Bacteria fertilize the soil and provide plants with nutrients which are rich in nitrogen; plants feed bacteria with sugar.

Interaction: Some of these organisms don´t move, some swim by means of flagella and some slide over surfaces. They live in all types of environments, even extreme ones, such as thermal waters.

Reproduction: Bacteria reproduce asexually through successive cell divisions. In this way they can form groups of millions, and these groups are called colonies.

Reproduction of bacteria

Types of bacteria Coccus, spherical bacteria Bacillus, rod shaped bacteria

Spirillum, bacteria with a helical or spiral shape Vibrio, curved bacteria

The Protoctist KingdomProtoctists are unicellular and multicellular organisms. They are eukaryotes and very simple and they never form tissues.

Protozoa and AlgaeProtozoa: Protozoa are unicellular eukaryotic beings and most of them are heterotrophs. They can be found in salt water, in pools or on the ground, except for few that live inside other living things, to which they cause harm.

Nutrition. Some protozoa feed on small particles found in their environment. Most are hunters and they feed on micro-organisms. A few are parasites and cause illnesses such as malaria.

Interaction. Some protozoa are immobile but most move using different mechanisms (see the picture on the following page).

Reproduction. They reproduce by dividing their cellular body into two or more daughter cells.

Algae: Algae are eukaryotic autotrophic beings. Their cells have walls, like plant cells. Most are unicellular and they usually form colonies but the best known algae are multicellular (see picture on the following page).

They perform photosynthesis because their cells contain chloroplast. Most are aquatic (from fresh water or salt water).

Algae have been used in food for centuries. For example, a type of gel is extracted from them, which is used to cultivate bacteria and make ice-cream.The main function of algae in nature is to feed aquatic herbivores. When some algae reproduce excessively they can cause serious problems in lakes and swamps.

Movement mechanisms of protozoaUsing a flagellum - Using pseudopods - Using cilia

Multicellular algae

Red algae: Most of the species are marine and they are red because they have a red pigment.

Brown algae: Most are marine. They are brown due to a brown pigment that is found the chloroplast.

Green algae: They can live in the sea and also in fresh water. They are green because they have a green pigment called chorophyll.

The Fungi Kingdom

Fungi are eukaryotic heterotrophic organisms. Some are unicellular, such as yeast, and others are multicellular; they don´t form tissues. Mushrooms are fungi. Their cells have a cellular wall, but they are different to plant cells.

They vital functions of fungiSome multicellular fungi are made up of fine threads called hyphae. It is easy to see them in moulds.

When the hyphae are packed tightly together, they form the mycelium. Example: mushrooms.

Nutrition:

Fungi are heterotrophic. They feed in different ways:

Saprotrophs feed on remains of dead organisms, like the remains of plants and animals.

Parasites feed on plants or living organisms, and they cause illnesses. Symbionts feed by associating with autotrophic organisms, which provide them with

the food they need.

Reproduction:

Fungi produce special types of cells to reproduce, called spores, from which a new fungus is created.

Interaction:

They usually live in the soil, in dark, damp places.

Some types of fungi

Fungi that form mushrooms and their reproduction

Moulds - Yeasts

The Plant Kingdom

Plants are eukaryotic multicellular organisms. They are also photosynthetic.

Parts of a plantA typical plant has organs, such as roots, a stem and leaves.

The root: The root secures the plant to the ground and absorbs water and mineral nutrients from it.

The stem: The stem supports leaves, branches and fruits. Leaves: The leaves are where photosynthesis and transpiration (the elimination of

excess water by evaporation of vapour) take place. Flowers: The flowers of a typical plant have a calyx (or set sepals), a corolla (or set of

petals), male sex organs (the stamen), and female sex organs (pistils).

The vital functions of a plant Nutrition: Plants are autotrophs because they make their own food through

photosynthesis. Reproduction: Their reproduction is sexual (through seeds) or asexual (through spores

or with fragments of their bodies, for example stem cuttings). Interaction: They live attached to the soil and they can´t move. They can, however,

make some movement, such as growing towards light or closing their leaves when touched.

Classification of plantsPlants can be classified into two groups:

Plants with seeds: They are the plants which have adapted best to the environment because they have flowers which contain reproductive organs and they have seeds which propagate better than spores. Spermatophytes are divided into two groups: plants with bare seeds called gymnosperms, and plants which have seeds inside a fruit called angiosperms.

Plants without seeds: These are plants without flowers, which reproduce through spores and need to live in wet environments to be able to reproduce.

Parts of a plant

Leaves Flowers

Plants with seedsGymnosperms are plants with bare seeds. Angiosperms are plants with seeds enclosed inside fruits.

Characteristics of gymnosperms

Characteristics of gymnospermsConifers are the most abundant gymnosperms. They are called conifers because their flowers group together to make cones. There are huge woods of conifers in cold regions of northern hemisphere. Pine trees, cypresses and junipers are conifers. Gymnosperms have the following characteristics:

They are woody plants. They are usually large shrubs and trees. They have thin, waterproof leaves so they can live in extreme temperatures. Their

leaves are green all year round. Their flowers are called cones. They are unisexual - they have male reproductive

organs and female reproductive organs separated in different flowers. Their flowers don´t have calyx or corolla. Their seeds aren´t protected inside a fruit.

Characteristics of angiospermsAngiosperms are the most numerous plants and they adapt well to the terrestrial environment: they can grow in cold, high mountains or in warm tropical areas. Angiosperms have the following characteristics:

Most are deciduous trees – they lose their leaves in winter They are herbs, shrubs and trees. Their flowers have calyx and corolla. They can be unisexual or hermaphrodite.

Hermaphrodite plants have the male reproductive organ (stamens) and the female reproductive organ (carpel) in the same flower. The seeds are protected inside fruit. After fecundation, the ovule changes into the embryo of the new plant. The carpel changes into the fruit and this protects the seed and helps to disseminate it.

Plants with seeds

Gymnosperms Male cone

Developed female cone

Angiosperms

Almond flower

fruit

Plants without seeds

Plants without seeds

Mosses Mosses are plants without tissues or organs. They reproduce by spores which are

formed in a capsule. These plants absorb water and all the substances they need through their whole

surface. These substances are small so that they can be distributed throughout the plant. Look at the diagram below to see the structure of moss.

Ferns Ferns are plants with roots, stems and leaves. The stem of a fern is called the rhizome, and it grows horizontally underground. Large

leaves, called fronds, grow from the stem. They reproduce by spores which are formed and which grow in a structure called the

sorus, on the underside of the fronds.

Moss Fern